The launch began a 13-day flight to the International Space Station and the second of five shuttle missions planned for 2010.

According to a NASA press release, discovery is scheduled to dock to the space station at 03:44 a.m. on Wednesday, April 7. The shuttle will deliver science experiments, equipment and supplies to the station.

"The crew of STS-131 is really honoured to represent the thousands of dedicated people that make up the entire NASA, JAXA and contractor workforces," Commander Alan Poindexter said in the release.

The flight will include three spacewalks to switch out a gyroscope on the station's truss, or backbone, install a spare ammonia storage tank, and retrieve a Japanese experiment from the station's exterior.

Inside the shuttle's cargo bay is the multi-purpose logistics module Leonardo, a pressurized "moving van" that will be attached to the station temporarily on April 7 and returned to the shuttle's cargo bay Thursday, April 15, it said.

The module is filled with supplies, new crew sleeping quarters and science racks that will be transferred to the station's laboratories. This is the final compliment of laboratory facilities that will complete the station's overall research capabilities.

Discovery's astronauts surveyed their ship for signs of launch damage, but the job was complicated by the failure of the space shuttle's big dish antenna.

Without the antenna, the seven astronauts have no way to send or receive big packages of information, like the images of the shuttle's wings and nose that are usually sent immediately to Mission Control.

Instead, commander Alan Poindexter and his crew had to store the data on 40-minute tapes that were fed, in turn, into a computer for digital conversion. In all, six tapes were filled, containing 35 to 40 gigabytes of information. All that information will be relayed once the shuttle reaches the International Space Station Wednesday, delaying analysis.

The rendezvous was expected to be trickier than usual, given the antenna trouble. The antenna is supposed to provide radar tracking as the shuttle approaches the station, from 40 kilometers out. Engineers had little confidence the system would be working by then.

Mission Control said the astronauts could rely on other tools, and stressed the linkup would not be any more dangerous.

"We're planning on getting there on time," Poindexter assured flight controllers on Tuesday. He said he trained for just such an event, two weeks ago back in Houston.